Integrated circuit package separators

ABSTRACT

An integrated circuit package separator for separating integrated circuit packages from a board includes a base, a support over the base, and a pair of pneumatic actuators including first and second lift members laterally spaced from the base and beneath respective ends of a pair of opposing ends of the support. The first and second lift members are configured to vertically displace the support and lift the support off the base by contacting the support. Individual actuators of the pair include release valves configured to equilibrate a back-pressure of the individual actuators to ambient during lifting of the support. The separator includes a cutting mechanism configured to cut the board while the board is over the upper surface of the support to separate the integrated circuit packages from one another.

CROSS REFERENCE TO RELATED APPLICATION

This patent application resulted from a divisional of U.S. patentapplication Ser. No. 09/533,058, filed on Mar. 22, 2000 U.S. Pat. No.6,718,858, entitled “Integrated Circuit Package Separators”, namingJason E. Tripard as inventor; which resulted from a divisionalapplication of U.S. patent application Ser. No. 09/176,479 (now U.S.Pat. No. 6,277,671), filed Oct. 20, 1998, entitled “Methods of FormingIntegrated Circuit Packages”, naming Jason E. Tripard as inventor; thedisclosures of which are incorporated by reference herein.

TECHNICAL FIELD

Aspects of the invention relate to apparatuses for separating integratedcircuit packages.

BACKGROUND OF THE INVENTION

Circuit constructions having integrated circuit (IC) chips bonded tocircuit boards (such as SIMMs and DIMMs) can be fabricated by joining ICchips on a single large circuit board comprising a plurality of theconstructions. The circuit board can be subsequently cut to separatediscrete constructions from one another. The discrete constructions arereferred to herein as integrated circuit packages. The smaller theindividual circuit packages, the more likely it is for industryprocessing to utilize the above-described method of forming the packageson a single large board and subsequently cutting individual packagesfrom the board.

An exemplary prior art process of separating integrated circuit packagesis described with reference to FIG. 1. FIG. 1 illustrates a boardassembly 10 having a plurality of IC chips 12 (only some of which arelabeled) bonded thereto. Chips 12 are aligned into individual IC packageconfigurations 14 (only some of which are labeled) to form a repeatingpattern of integrated circuit packages 14 across the board assembly 10.Dashed lines 16 are shown to illustrate the boundaries betweenindividual IC packages 14. In the shown exemplary embodiment, assembly10 comprises three separate circuit boards 11, 13 and 15. The number andsize of individual circuit boards can vary depending on the number andsize of IC packages that are ultimately to be formed.

Each of boards 11, 13 and 15 comprises a pair of lateral waste sections21, 23 and 25, respectively. The lateral waste sections 21, 23 and 25are separated from the remainder of boards 11, 13 and 15, respectively,by imaginary dashed lines 20, 22 and 24. In further processing, theindividual IC packages 14 are separated from one another by cuttingthrough boards 11, 13 and 15 along the regions illustrated by dashedlines 16. During the cutting to separate IC packages 14 from oneanother, boards 11, 13 and 15 are also cut along regions illustrated bydashed lines 20, 22 and 24 to remove waste portions 21, 23 and 25 fromthe lateral sides of the boards, and accordingly from lateral edges ofthe ultimately formed IC packages.

Orifices 19 (only some of which are labeled) are provided throughoutcircuit boards 11, 13 and 15. Specifically, pairs of orifices 19 areprovided in each IC package 14, and at least two orifices 19 areprovided in each of waste portions 21, 23 and 25.

FIG. 1 further illustrates an IC package separator 40 comprising acutting mechanism 42 (shown schematically as a cutting wheel, althoughother cutting mechanisms, such as, for example, router bits or linearblades, are known to persons of ordinary skill in the art), a retainingtable 44, and a control mechanism 45 configured to control orientationof cutting wheel 42 relative to table 44. Retaining table 44 cancomprise, for example, an x-y table (i.e., a table horizontallyadjustable in x and y directions; an “X”, “Y” and “Z” axis system isillustrated in a lower corner of FIG. 1). Control mechanism 45 cancontrol the x and y orientation of table 44 and the z (i.e., vertical)orientation of cutting mechanism 42 to precisely cut a board retained ontable 44. Table 44, cutting mechanism 42, and control mechanism 45 canbe comprised by commercially available cutting systems, such as, forexample, Advanced Technology Incorporated's CM101 single spindle router(or, more generally, a circuit board depanelization router).

FIG. 1 also illustrates that table 44 comprises an upper platform 46. Asubplate 48 is provided over platform 46, and a stripper plate 50 isprovided over subplate 48. Subplate 48 comprises a plurality of upwardlyextending pins 60 (only some of which are labeled), and stripper plate50 comprises a number of orifices 62 configured to slide over pins 60.Subplate 48 is retained on table 44 by downwardly extending pins (notshown) which are aligned with and precisely received within orifices(not shown) extending within platform 46 of table 44.

Orifices 19 of boards 11, 13 and 15 align with pins 60. In operation,boards 11, 13 and 15 are slid over pins 60 until the pins protrudethrough orifices 19. Typically, orifices 19 are only about 0.003 incheswider than pins 60 to insure tight alignment of boards 11, 13 and 15with subplate 48. After boards 11, 13 and 15 are retained on table 44 bypins 60, cutting mechanism 42 is utilized to cut along the regionsillustrated by dashed lines 16, 20, 22 and 24. Such cutting separatesdiscrete integrated circuit packages 14 from one another, as well asfrom waste regions 21, 23 and 25. The separated circuit packages areretained on table 44 by pins 60 extending through the packages.Specifically, each of individual packages 14 comprises a pair oforifices 19 and is thereby retained on table 44 by a pair of pins 60.

After the IC packages are separated from one another, stripper plate 50is manually lifted off of subplate 48 to lift the IC packages 14 frompins 60. Once stripper plate 50 is lifted off from pins 60, theindividual IC packages can be separated from stripper plate 50. Anexemplary method of removing the IC packages from stripper plate 50 isto tilt plate 50 and allow the packages to slide off plate 50. After thepackages 14 are removed, plate 50 can be returned to over 48 and usedagain for separating IC packages.

Difficulties can occur in utilizing the assembly of FIG. 1 forseparating IC packages. For instance, separated IC packages can bebroken as stripper plate 50 is lifted from subplate 48. It would bedesirable to reduce or eliminate such problems.

SUMMARY OF THE INVENTION

An integrated circuit package separator for separating integratedcircuit packages from a board, the separator including a base, a supportover the base, and a pair of pneumatic actuators including first andsecond lift members laterally spaced from the base and beneathrespective ends of a pair of opposing ends of the support, wherein thefirst and second lift members are configured to vertically displace thesupport and lift the support off the base by contacting the support.Individual actuators of the pair include release valves configured toequilibrate a back-pressure of the individual actuators to ambientduring lifting of the support; and a cutting mechanism configured to cutthe board while the board is over the upper surface of the support toseparate the integrated circuit packages from one another.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

FIG. 1 is a diagrammatic, perspective, exploded view of a prior art ICpackage separator and circuit board assembly.

FIG. 2 is a diagrammatic top view of an IC package separator of thepresent invention.

FIG. 3 is a diagrammatic, perspective, exploded view of an IC packageseparator of the present invention with a stripper plate of the presentinvention and a circuit board.

FIG. 4 is a view of the FIG. 3 assembly with the circuit board retainedon the IC separator.

FIG. 5 is a view of the FIG. 4 assembly after the retained circuit boardis cut to separate individual IC packages from one another.

FIG. 6 is a view of the FIG. 5 assembly after a stripper plate is liftedto release separated IC packages from retaining pins.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

This disclosure of the invention is submitted in furtherance of theconstitutional purposes of the U.S. Patent Laws “to promote the progressof science and useful arts” (Article 1, Section 8).

An IC package separator of the present invention and a method ofoperation of such separator are described below with reference to FIGS.2-6. In referring to FIGS. 2-6, similar numbering to that utilized abovein describing prior art FIG. 1 will be used, with differences indicatedby the suffix “a” or by different numerals.

Referring to FIG. 2, a separator 100 of the present invention is shownin top view. Separator 100 comprises a table 44 a and a subplate 48 aprovided over table 44 a. Table 44 a can comprise, for example, an x-ytable similar to the table 44 described above with reference to FIG. 1.Subplate 48 a, like the above-described substrate 48 of FIG. 1, can bejoined to table 44 a through a plurality of downwardly extending pins(not shown), and comprises a plurality of upwardly extending pins 60(only some of which are labeled) configured to retain a circuit boardassembly (not shown).

Subplate 48 a differs from subplate 48 of FIG. 1 in that subplate 48 acomprises notches 102 at its ends. Notches 102 are provided to allowroom for a pair of forcer plates 104 and 106 to move vertically (in andout of the page of FIG. 2) relative to table 48 a. Forcer plates 104 and106 comprise upwardly extending pins 108 and 110, respectively. Baseplate 48 a comprises an upper planar surface 115, and forcer plates 104and 106 comprise upper planar surfaces 117 and 119, respectively. Upperplanar surfaces 115, 117 and 119 ultimately support a circuit boardassembly (not shown in FIG. 2). Planar surfaces 115, 117 and 119 arepreferably substantially coplanar with one another to avoid distorting(e.g., bending) a supported circuit board assembly.

Forcer plates 104 and 106 are connected to actuators 112 and 114,respectively, configured to vertically displace forcer plates 104 and106. In the exemplary shown embodiment, forcer plates 104 and 106 areconnected to the actuators with screws 116. It is to be understood,however, that other mechanisms could be utilized for joining forcerplates 104 and 106 to actuators 112 and 114, including, for example,welding.

Actuators 112 and 114 are pneumatic (preferably air-powered) andconnected to a gas source 120. An advantage of utilizing air poweredactuators is that most wafer fabrication plants have a source of cleandry air available. Accordingly, it is relatively convenient to coupleair powered actuators 112 and 114 into existing fabrication plants bysimply connecting them to existing air lines. However, it is to beunderstood that the actuators can be powered by other sources besidesair, including, for example, other fluids, such as liquids, as well asnon-pneumatic and non-hydraulic sources, such as, for example,electricity.

Separator apparatus 100 comprises a cutting assembly (not shown in FIG.2) and a controller (not shown in FIG. 2), analogous to the cuttingassembly 42 and controller 45 of FIG. 1.

Referring to FIG. 3, IC circuit package separator 100 is shown inexploded view with a circuit board assembly 10 identical to the assemblydescribed above with reference to FIG. 1.

A stripper plate 50 a is provided between subplate 48 a and circuitboard assembly 10. Stripper plate 50 a is similar to the stripper plate50 of FIG. 1 in that plate 50 a comprises a plurality of orifices 62configured for receipt of pins 60. However, stripper plate 50 a differsfrom plate 50 of FIG. 1 in that plate 50 a also comprises orifices 122configured for receipt of upwardly extending pins 108 and 110 of forcerplates 104 and 106. Pins 108 and 110 are preferably tapered pins, suchas can be obtained from McMaster-Carr. Exemplary pins have a dimensionof 0.248 inches at base, 0.2324 inches at top, and a length of 0.75inches. The taper of the pins can assist in aligning support 50 a overthe pins during placement of support 50 a onto base 48 a.

Stripper plate 50 a further differs from plate 50 of FIG. 1 in thatplate 50 a is configured for receipt of a series of panels 132, 134 and136. Stripper plate 50 a can comprise, for example, static-reducedplastic having a thickness of greater than {fraction (3/16)} inches, andpanels 132, 134 and 136 can comprise, for example, aluminum. In theshown embodiment, panels 132, 134 and 136 are held to stripper plate 50a by a plurality of screws 138 (only some of which are labeled). It willbe recognized, however, that other mechanisms can be utilized forholding panels 132, 134 and 136 to stripper plate 50 a, includingriveting. Alternatively, panels 132, 134 and 136 can be molded as partof stripper plate 50 a.

Panels 132, 134 and 136 comprise ribs 140, 142 and 144, respectively(only some of which are labeled). Ribs 140, 142 and 144 can assist insupporting board assembly 10. Specifically, IC chips 12 are frequentlyprovided on both an upper surface of circuit board assembly 10, and abottom surface (not shown). Ribs 140, 142 and 144 (also referred to asblocks) have upper surfaces 141, 143 and 145, respectively, whichcontact the bottom surfaces of circuit boards 11, 13 and 15 at locationsbetween the IC chips 12 on the bottom of the board. Preferably, suchupper surfaces are provided at a height approximately equal to athickness of integrated circuit chip components 12. Accordingly, whenboards 11, 13 and 15 are rested on panels 132, 134 and 136,respectively, the boards rest on the upper surfaces of blocks 140, 142and 144 while leaving integrated circuit chip components on theunderside of boards 11, 13 and 15 extending between block upper surfaces141, 143 and 145 and panels 132, 134 and 136. An exemplary block height(or thickness) of blocks 140, 142 and 144 for a DRAM having IC chips 12with a TSOP dimensional package is 0.040 inches ±0.005 inches. Asanother example, if IC chips 12 have a SOJ dimensional package, theblock height is preferably 0.140 inches ±0.005 inches.

Blocks 140, 142 and 144 can be formed as one piece with panels 132, 134and 136. Alternatively, blocks 140, 142 and 144 can be formed asdiscrete pieces from panels 132, 134 and 136 that are subsequentlyfastened to the panels.

In the shown embodiment, blocks 140, 142 and 144 are provided in aone-to-one correspondence with integrated chip packages 14. Also, in theshown exemplary embodiment each of panels 132, 134 and 136 is identicalto one another, and in a one-to-one correspondence with individualboards 11, 13 and 15. It is to be understood, however, that theinvention encompasses other embodiments (not shown) wherein the blocksare not provided in a one-to-one correspondence with packages 14,wherein the panels are not identical to one another, and wherein thepanels are not in a one-to-one correspondence with the individualboards.

Pins 60 extend upwardly beyond upper surfaces 141, 143 and 145 of blocks140, 142 and 144, and are configured to retain circuit board assembly 10over stripper panel 50 a. In the shown embodiment, pins 60 do not extendthrough panels 132, 134 and 136. However, it is to be understood thatthe invention encompasses other embodiments wherein pins 60 do extendthrough such panels.

FIG. 3 shows a side perspective view of actuator 112. In such view itcan be seen that several ports 150, 152, 153, 154, 155 and 156 areprovided between actuator 112 and gas source 120. Valves (not shown) areprovided between source 120 and one or more of ports 150, 152, 153, 154,155 and 156. Such valves enable fluid to be selectively flowed fromsource 120 into one or more of ports 150, 152, 153, 154, 155 and 156 toselectively control raising and lowering of forcer plate 104 withactuator 112. For instance, flow of gas into port 152 can force apneumatic cylinder to lift forcer plate 104, and flow of gas into port150 can force the pneumatic cylinder to lower forcer plate 104.

Ports 154 and 156 are connected to release valves 163 and 165,respectively, which enable a pressure on at least one side of thepneumatic cylinder of actuator 112 to be maintained at ambient pressure(generally, about 1 atmosphere). Specifically, release valves 163 and165 comprise outlet ports 157 and 159, respectively, which vent to asurrounding environment. Persons of ordinary skill in the art willrecognize that one or more of ports 150, 157 and 159 are utilized as gasoutlet ports during lifting of forcer plate 104, and port 152 comprisesa gas inlet port during such lifting. In preferred embodiments of thepresent invention, the release valves are associated with an outlet sideof actuator 112 to enable equilibration of a pressure at such outletside to ambient prior to (and/or during) lifting of forcer plate 104.Specifically, the release valves enable gas to be drained from outletlines (more specifically, the gas is drained through ports 157 and 159which are open to ambient conditions) prior to, and/or during, liftingwith the actuator. Actuator 114 (FIG. 2) is preferably identical toactuator 112 and connected to an identical valve and port assembly asthat shown connected to actuator 112. Accordingly, actuator 114 is alsoconnected with release valves configured to equilibrate a back-pressureof the actuator to ambient prior to, and/or during, lifting of stripperpanel 50 a. The equilibration of pressure at the outlet ends of both ofactuators 112 and 114 to ambient during a lifting operation can enableboth actuators to have an identical back-pressure during the liftingoperation. This can facilitate having both actuators lift simultaneouslyand in unison. Such simultaneous lifting can avoid distortion (such as,for example, bending) of circuit board assembly 10 during the lifting.

Stripper plate 50 a has an upper planar surface 160 and a pair ofopposing ends 162 and 164. Opposing ends 162 and 164 overlie forcerplates 104 and 106, respectively. In operation, actuators 112 and 114are utilized to lift opposing ends 162 and 164 simultaneously and inunison. Such can be accomplished by, for example, maintainingapproximately equal gas pressure at both of actuators 112 and 114 duringlifting, and is found to reduce breakage of integrated circuit packagesrelative to prior art methods. The term “approximately” in the previoussentence is utilized to indicate the gas pressure at both actuators isequal within operational parameters.

A method of operation of separator 100 is described with reference toFIGS. 4-6. In referring to FIGS. 4-6, subplate 48 a is referred to as abase, and stripper plate 50 a is referred to as a support. Referringfirst to FIG. 4, circuit board assembly 10 is shown retained on support50 a. Specifically, circuit board assembly 10 is placed over supportupper surface 160 with pins 60 extending through orifices 19 of thecircuit boards 11, 13 and 15. Pins 60 and board assembly 10 are alignedsuch that each of the integrated circuit packages 14 is retained to thesupport 50 a by at least one pin, and, in the shown embodiment, isretained by 2 pins. In the FIG. 4 processing step, actuators 112 and 114(FIG. 2) are in a lowered position.

Referring to FIG. 5, the individual integrated circuit packages 14 areseparated from one another by cutting through boards 11, 13 and 15.

Referring to FIG. 6, actuators 112 and 114 (FIG. 2) are utilized tovertically displace support 50 a from base 48 a. Preferably, suchvertical displacement comprises lifting both of ends 162 and 164 ofsupport 50 a substantially simultaneously and substantially in unisonwith one another. (As used in the preceding sentence, the term“substantially” indicates that the lifting of both ends is simultaneousand in unison within operational parameters.) In exemplary applicationsthe upper surface 160 of support 50 a is level prior to the lifting andremains level during the lifting. The lifting of support 50 a releasesseparated circuit packages 14 from pins 60. After such release, support50 a can be, for example, manually lifted from pins 108 and 110, and theseparated packages removed from support 50 a.

In compliance with the statute, the invention has been described inlanguage more or less specific as to structural and methodical features.It is to be understood, however, that the invention is not limited tothe specific features shown and described, since the means hereindisclosed comprise preferred forms of putting the invention into effect.The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

1. An integrated circuit package separator for separating integratedcircuit packages from a board, the separator comprising; a base; aplurality of pins extending upwardly from the base; a support over thebase; a pair of pneumatic actuators including first and second liftmembers laterally spaced from the base and beneath respective ends of apair of opposing ends of the support, the first and second lift membersbeing configured to vertically displace the support and lift the supportoff the base by contacting the support, each of the pneumatic actuatorsincluding release valves configured to equilibrate a back-pressure ofeach of the pneumatic actuators to ambient during lifting of thesupport; a cutting mechanism configured to cut the board while the boardis over the upper surface of the support to separate the integratedcircuit packages from one another; and wherein the support comprises anupper surface and a plurality of holes extending therethrough, theplurality of pins being configured to extend through respective ones ofthe plurality of holes and upwardly beyond the upper surface of thesupport.
 2. The separator of claim 1, wherein the support and theplurality of pins being configured such that the plurality of pinsextend into the plurality of holes in the board when the board is placedover the upper surface of the support.
 3. The separator of claim 1,wherein the plurality of pins align with the board such that each of theseparated integrated circuit packages is retained to the support by atleast one pin.
 4. An integrated circuit package separator for separatingintegrated circuit packages from a board, the separator comprising: abase; a support over the base; a pair of pneumatic actuators includingfirst and second lift members laterally spaced from the base and beneathrespective ends of a pair of opposing ends of the support, the first andsecond lift members being configured to vertically displace the supportand lift the support off the base by contacting the support, each of thepneumatic actuators including release valves configured to equilibrate aback-pressure of each of the pneumatic actuators to ambient duringlifting of the support; a cutting mechanism configured to cut the boardwhile the board is over the upper surface of the support to separate theintegrated circuit packages from one another; and wherein the baseincludes a substantially planar upper surface, and the first and secondlift members each have a substantially planar upper surface, the planarsurfaces of the first and second lift members being substantially flushwith the planar upper surface of the base.
 5. An integrated circuitpackage separator, comprising: a base; a plurality of pins extendingupwardly from the base; a support over the base; a pair of pneumaticactuators configured to vertically displace the support and lift thesupport off the base; each actuator of the pair of pneumatic actuatorsincluding release valves configured to equilibrate a back-pressure ofeach actuator to ambient during lifting of the support such that theactuators lift respective opposing ends of the support substantiallysimultaneously and in unison; a cutting mechanism configured to cut aboard, having integrated circuit packages, while the board is over anupper surface of the support to separate the integrated circuit packagesfrom one another; and wherein the support comprises a plurality of holesextending therethrough, the plurality of pins being configured to extendthrough respective ones of the plurality of holes and upwardly beyondthe upper surface of the support.
 6. The separator of claim 5, whereinthe support and the plurality of pins being configured such that theplurality of pins extend into the plurality of holes in the board whenthe board is placed over the upper surface of the support.
 7. Theseparator of claim 5, wherein the plurality of pins align with the boardsuch that each of the separated integrated circuit packages is retainedto the support by at least one pin.
 8. An integrated circuit packageseparator, comprising: a base; a support over the base; a pair ofpneumatic actuators configured to vertically displace the support andlift the support off the base; each actuator of the pair of pneumaticactuators including release valves configured to equilibrate aback-pressure of each actuator to ambient during lifting of the supportsuch that the actuators lift respective opposing ends of the supportsubstantially simultaneously and in unison; a cutting mechanismconfigured to cut a board, having integrated circuit packages, while theboard is over an upper surface of the support to separate the integratedcircuit packages from one another; and wherein the base and each of theactuators have a substantially planar upper surface, the planar surfacesof the actuators being substantially flush with the planar upper surfaceof the base.